海水酸化及升温对刺参稚参生长和变色的影响

海洋酸化和海洋变暖是当下及未来海洋生物及其依存生态系统面临的主要环境压力和生态问题。当前,海洋生物早期发育气候变化生物学的研究主要集中于海洋酸化的影响,为了更好地探究海洋气候变化对海洋生物的影响,有必要研究海洋酸化和变暖联合作用下海洋生物的生态响应。以受精后24天的刺参稚参为研究对象,通过模拟当前和本世纪末海洋环境,观察海水酸化和升温对刺参稚参在体色发育关键时期生长、发育及体色变化的影响。实验设置对照组(大连近海水温,pCO₂ 400 mg·kg^-1)、升温组(对照组水温+2℃,pCO₂ 400 mg·kg^-1)、酸化组(对照组水温,pCO₂ 1000 mg·kg^-1)、酸化升温组(对照组水温+2℃,pCO₂ 1000 mg·kg^-1)。结果表明:温度升高2℃能够显著提高稚参发育速率,体色变化加快; pH值降低0.23个单位显著延迟稚参生长,体色变化减缓,个体间体重差异变大;升温2℃能抵消pH降低0.23个单位对...     

南移刺参摄食三种沉积物饵料下的生长和能量收支比较

为研究不同沉积物对南移刺参的影响,测定了南移刺参对三种不同沉积物(海区沉积物、对虾养殖池沉积物、人工配制沉积物)的摄食,吸收效率和能量收支。结果表明,规格为26.11±1.5g的南移刺参在温度为17±1℃时,不同组别南移刺参对不同种沉积物的摄食率无显著差异(P>0.05),对虾组和人工组南移刺参同化效率和特定生长率显著高于海区组(P<0.05),且对虾组同化效率和特定生长率最高。通过对能量收支方程的探究,各组别代谢能无显著差异(P>0.05),对虾组南移刺参生长能显著高于其他两组(P<0.05),其能量收支方程为:100C=12.35G+34.91F+8.05U+44.69R。研究表明,特定养殖条件下,用虾塘沉积物喂食南移刺参时,刺参摄食能量较多的分配至生长,生长速率较快,利用虾塘沉积物作为饵料是一种可取模式。     

夏眠对刺参(Apostichopus japonicus (Selenka))能量收支的影响

夏眠是刺参最重要的生理特征;水温升高是其夏眠的主要诱发因子,而夏眠的临界温度与刺参体重密切相关。为揭示刺参夏眠对其能量利用对策的影响,测定了2种体重规格(134.0±13.5)g和(73.6±2.2)g刺参在10、15、20、25℃和30℃5个温度梯度下的能量收支。结果表明,温度和体重及其交互作用对刺参能量的摄入均有显著影响;而温度是影响其摄食能分配的主要因素。研究发现,刺参在非夏眠期、夏眠临界期和完全夏眠期的能量利用对策有所不同:在非夏眠期,刺参摄食能支出的最大组分是粪便能,占摄食能的比例超过50%,其次为呼吸耗能,占19.8%～39.4%,而生长能和排泄能占的比例较小,分别为5.7%～10.7%和2.9%～3.7%;在夏眠临界温度下,呼吸和排泄耗能占摄食能的比例均显著增大(分别为88.3%和13.6%),而生长能所占比例降为负值(-55.3%),刺参表现为负生长;而在夏眠期,刺参的摄食能和排粪能为零,为维持其基本生理活动,不得不动用以往贮存于体内的能量,消耗于呼吸和排泄等生理过程,供维持生命之用。总之,从能量生物学的角度看,夏眠的主要生态学意义在于刺参长时间处于相对高温环境,进而导致摄食受阻条件下的一种能量节约方式。     

摄食水平对中华鳖稚鳖生长、氮排泄和能量收支的影响

在 30℃水温下进行摄食 -生长实验 (实验周期为 5 6d) ,设饥饿、1%、2 %、4 %和饱食 5个摄食水平 ,研究了中华鳖稚鳖 (39 5 4— 4 4 2 2g)的生长和能量收支。结果表明 ,中华鳖稚鳖的特定生长率随摄食水平的增加 ,其湿重、干物质、蛋白质和能量的特定生长率均呈二次曲线增加 ,其中干物质的特定生长率 (SGRdr)与摄食率 (Rl)的关系式为 :SGRdr=- 1 8799 1 0 795Rl- 0 0 832Rl2 (r=0 90 6 ,n =2 5 ,P <0 0 1) ;除干物质转化效率外 ,湿重、蛋白质和能量的转化效率在 2 %组均达到最大 ,分别为 36 31%、2 1 4 7%和 2 8 10 % ;除能量转化效率外 ,4 %组湿重、干物质和蛋白质的转化效率与最大值均无显著差异 ;摄食水平对中华鳖稚鳖总氮排泄率、氨氮排泄率、尿素氮排泄率以及氨氮占总氮排泄率的比例均有显著影响 (P <0 0 1) ,除氨氮占总氮比例外其他指标均随摄食水平的增加而增加 ,氨氮比例在饥饿组最高为 5 5 83% ,由饥饿到饱食其变化范围是 4 4 5 0 %— 5 5 83% ;总氮排泄率、氨态氮排泄率和尿素氮排泄率的变动范围分别是 19 81%— 6 5 87%、9 4 4 %— 36 31%和 8 2 4 %— 2 9 5 6 % ,回归分析表明 ,幼鳖的总氮排泄率 (μmol/g·d) (G N)、氨氮排泄率 (μmol/g·d) (NH3 N)及尿素氮排泄率 (μmol/g·     

夏眠对刺参(Apostichopus japonicus(Selenka))能量收支的影响

夏眠是刺参最重要的生理特征;水温升高是其夏眠的主要诱发因子,而夏眠的临界温度与刺参体重密切相关。为揭示刺参夏眠对其能量利用对策的影响,测定了2种体重规格（134.0±13.5）g和(73.6±2.2）g刺参在10、15、20、25 ℃和30 ℃ 5个温度梯度下的能量收支。结果表明,温度和体重及其交互作用对刺参能量的摄入均有显著影响;而温度是影响其摄食能分配的主要因素。研究发现,刺参在非夏眠期、夏眠临界期和完全夏眠期的能量利用对策有所不同：在非夏眠期,刺参摄食能支出的最大组分是粪便能,占摄食能的比例超过50%,其次为呼吸耗能,占19.8%~39.4%,而生长能和排泄能占的比例较小,分别为5.7%~10.7%和2.9%~3.7%;在夏眠临界温度下,呼吸和排泄耗能占摄食能的比例均显著增大（分别为88.3%和13.6%）,而生长能所占比例降为负值（-55.3%）,刺参表现为负生长;而在夏眠期,刺参的摄食能和排粪能为零,为维持其基本生理活动,不得不动用以往贮存于体内的能量,消耗于呼吸和排泄等生理过程,供维持生命之用。总之,从能量生物学的角度看,夏眠的主要生态学意义在于刺参长时间处于相对高温环境,进而导致摄食受阻条件下的一种能量节约方式。     

不同温度对中国对虾生长及能量收支的影响

研究了18～34℃6个不同恒温下中国对虾(Fenneropenaeus chinensis)的生长、饵料转化率及能量收支。结果表明,中国对虾的体重及能量特定生长率分别变动在1．22％～3．27％和1．33％～1．45％之间,在18～31℃温度范围内随温度升高而升高,34℃下则显著下降．对虾的摄食量及对饵料的消化率总体上随温度升高而升高,但在34℃下则有所降低;饵料重量转化率和能量转化率分别在28．99％～53．09％和15．70％～7．24％之间,总体上随温度升高而有所下降．根据拟合的多项式方程推算得到的中国对虾的最佳生长温度为29．7℃,生长能和呼吸能的变化主导着中国对虾的能量收支模式,随温度升高生长能占摄食能的比例逐渐降低,而呼吸能比例则逐渐升高。本研究表明,对虾在适宜温度下获得的较高生长率主要归因于较高的摄食量和食物消化率。     

皱纹盘鲍的个体能量收支

对皱纹盘鲍的呼吸、摄食、生长及能量收支等实验研究表明, 鲍的耗氧率与壳长、体重、温度及昼夜变化有关, 耗氧率与壳长、体重均呈幂函数关系, 一天中16~4时(夜间)耗氧率高于4~16时(白天)且在18~20时达峰值.同温度下鲍日摄食率与体重呈幂指数关系, 日(相对)摄食率随温度升高而增加, 而日相对摄食率、日相对生长率均随壳长、体重增加呈下降趋势.鲍在14~20℃内对海带的总转化效率为53%.鲍软体部、海带及鲍粪便干品的比能值分别为19.2、8.57和7.23kJ·g^-1.14~20℃皱纹盘鲍摄入能量的34.6~48.6%为粪能, 22.0~38.2%的能量用于自身代谢, 5.6~28.2%用于贝体软体部的生长.     

饥饿对牙鲆幼鱼补偿生长、生化组成及能量收支的影响

在水温(23.0±1.0)℃条件下,以鲜杂鱼(x)和配合饲料(P)为饵料,采用室内循环流水的试验方法研究饥饿后再投喂对牙鲆幼鱼补偿生长、生化组成及能量收支模式的影响.结果表明:试验组S1F5、S5F25均表现出完全补偿生长现象,且S1F5组主要通过提高摄食率(FR)来实现补偿生长,而S5F25组主要通过提高食物转化率(FCE)来实现补偿生长;经补偿生长后,各试验组鱼体的生化组成与对照组均无显著差异(P>0.05);经饥饿处理后牙鲆幼鱼生长能占摄食能的比例增加,用于排泄和代谢的比重有所下降.     

光周期对中华鳖稚鳖摄食、生长和能量转换的影响

在水温２９±１℃,光照强度５００ｌｘ的条件下,研究了不同光周期对中华鳖稚鳖的最大日摄食量、最大日摄食率、特定生长率、同化效率、消化时间和生长效率的影响。结果表明,光周期对中华鳖稚鳖的上述各指标均无显著影响。随体重的增加,中华鳖稚鳖的最大日摄食量逐渐增大,而最大日摄食率则逐渐减少。在人工养殖中华鳖稚鳖过程中,光照周期的选择是次要的     

棉铃虫的能量收支

在25℃下用人工饲料和自然食物饲养棉铃虫,分析通过虫体的能流。取食紫云英-麦胚人工饲料时,整个幼虫期摄入能量(Ⅰ)11,852焦耳,其中51.3%随排泄物排出体外(FU),22.2%被利用并转移到虫体组织内(Pg),0.5%被利用、但在蜕皮时又随头壳、表皮等脱离虫体(Pe),其余26%的能量被用于维持幼虫的生命活动并通过呼吸消失?。幼虫转化能量的毛生态效率(P/I)和净生态效率(P/A)分别是22.7%和46.6%。取食嫩棉叶/棉桃时,幼虫期摄入能量(Ⅰ)19,356焦耳,其中FU,Pg,Pe,R分别占35.3%,11.3%,0.5%和53.0%,P/I,P/A分别为11.7%和18.0%。 两组棉铃虫蛹和成虫期能量收支的差别不大,蛹—成虫期的能量转化效率在69—75%(雌)和64—69%(雄)左右。雌性成虫体内的能量约有40%(人工饲料组)—50%(自然饲料组)被用于繁衍后代。 同其它鳞翅目昆虫相比,人工饲料组棉铃虫幼虫对能量的转化效率属中等水平;棉花虽然是棉铃虫的自然寄主植物,但幼虫取食这种食物时对能量的转化效率相当低。     

Effect of increased pCO2 in seawater on survival rate of different developmental stages of the harpacticoid copepod Tigriopus japonicus

The rapid increase in carbon dioxide levels in seawater is causing ocean acidification and is expected to have significant effects on marine life. To explore the ability of the harpacticoid copepod Tigriopus japonicus to adapt to an increased concentration of dissolved carbon dioxide (CO₂) in seawater, we compared the survival rates of adult and nauplius stages at 400, 1000, and 1550?ppm pCO₂ over a 14-day period. The survival rate of T. japonicus dramatically decreased over time with increase in pCO₂ concentration. At 1550?ppm, the survival rate showed a decrease of more than 20% at the end of the experimental period over that at 400?ppm. Furthermore, the survival rate decreased by a greater amount at all concentrations in nauplii than in adults, with a greater effect in wild-collected specimens than in culture-derived individuals. The results suggest that future ocean acidification may negatively influence the sustainability of T. japonicus and thus may eventually influence benthic ecosystems.     

仿刺参基因组DNA提取方法改进

开发了利用仿刺参管足活体取样提取基因组DNA的方法。按照传统方法提取仿刺参基因组DNA需要杀死实验对象并剖取体腔内纵肌(通常100mg)作为实验材料,并且实验过程中常常因为仿刺参的生物学性状而影响最终实验效果。以仿刺参在生活状态下拔取少量管足(10～20mg即可)作为取样源,在保持仿刺参的生活力不受影响的同时提高了取样效率。对仿刺参基因组DNA的提取方法进行了改进优化,并在常规海洋动物基因组DNA提取方法的基础上增加了部分操作步骤。与常规的基因组DNA提取方法相比,改进后的方法获取的基因组DNA完全符合后续实验要求。而且可随时根据即时效果(中间检测)和后续实验要求调整实验步骤,更增加了实验的可操作性。     

Complex and interactive effects of ocean acidification and warming on the life span of a marine trematode parasite

Human activities have caused an increase in atmospheric CO₂ over the last 250 years, leading to unprecedented rates of change in seawater pH and temperature. These global scale processes are now commonly referred to as ocean acidification and warming, and have the potential to substantially alter the physiological performance of many marine organisms. It is vital that the effects of ocean acidification and warming on marine organisms are explored so that we can predict how marine communities may change in future. In particular, the effect of ocean acidification and warming on host-parasite dynamics is poorly understood, despite the ecological importance of these relationships. Here, we explore the response of one himasthlid trematode, Himasthla sp., an abundant and broadly distributed species of marine parasite, to combinations of elevated temperature and pCO₂ that represent physiological extremes, pre-industrial conditions, and end of century predictions. Specifically, we quantified the life span of the free-living cercarial stage under elevated temperature and pCO₂, focussing our research on functional life span (the time cercariae spend actively swimming) and absolute life span (the period before death). We found that the effects of temperature and pCO₂ were complex and interactive. Overall, increased temperature negatively affected functional and absolute life span, e.g. across all pCO₂ treatments the average time to 50% cessation of active swimming was approximately 8 h at 5 °C, 6 h at 15 °C, 4 h at 25 °C, and 2 h at 40 °C. The effect of pCO₂, which significantly affected absolute life span, was highly variable across temperature treatments. These results strongly suggest that ocean acidification and warming may alter the transmission success of trematode cercariae, and potentially reduce the input of cercariae to marine zooplankton. Either outcome could substantially alter the community structure of coastal marine systems.     

皱纹盘鲍的个体能量收支

对皱纹盘鲍的呼吸、摄食、生长及能量收支等实验研究表明, 鲍的耗氧率与壳长、体重、温度及昼夜变化有关, 耗氧率与壳长、体重均呈幂函数关系, 一天中16~4时(夜间)耗氧率高于4~16时(白天)且在18~20时达峰值.同温度下鲍日摄食率与体重呈幂指数关系, 日(相对)摄食率随温度升高而增加, 而日相对摄食率、日相对生长率均随壳长、体重增加呈下降趋势.鲍在14~20℃内对海带的总转化效率为53%.鲍软体部、海带及鲍粪便干品的比能值分别为19.2、8.57和7.23kJ·g^-1.14~20℃皱纹盘鲍摄入能量的34.6~48.6%为粪能, 22.0~38.2%的能量用于自身代谢, 5.6~28.2%用于贝体软体部的生长.     

刺参甘露糖结合凝集素的生物信息学分析

甘露糖结合凝集素(mannan-binding lectin,MBL)属于C型动物凝集素超家族,特异地结合甘露糖。MBL是宿主起始免疫系统一个重要成分,因此近年来逐渐成为研究的热点。采用生物信息学技术对刺参(Apostichopus japonicus)MBL(AJ-MBL)的两个基因编码的蛋白质结构和功能进行了分析,包括信号肽、分子量、等电点、跨膜结构域、糖基化和磷酸化位点、二级结构和三级结构等,旨在了解其结构特征,为动物免疫反应方面研究提供理论基础。     

The Syndrome of Sea Cucumber (Apostichopus japonicus) Infected by Virus and Bacteria

A outbreak of disease with symptoms of evisceration and skin ulteration led to mass mortality in sea cucumber Apostichopus japonicus cultivated in indoor ponds near the Dalian coast from December 2004 to April 2005. Spherical virus particles with a diameter of 75-200 nm were found in the cytoplasm of cells in the water-system, the alimentary canal and in the respiratory trees of the diseased and dying sea cucumber individuals by electron microscopic observation of ultrathin sections. Examination by negative stained samples revealed that all the diseased sea cucumbers were infected by the virus, while the healthly ones cultivated outside the contagious area were not. Two bacterial strains were also isolated from the diseased animals. When exposed to a medium containing the virus particles, regardless of whether the bacterial suspension was added,healthy sea cucumbers exhibited identical disease symptoms as the ones in the indoor ponds, and had a mortality of 90%-100%. However, when exposed to a medium in which there was only one of the two bacterial strains, 30%-80% of the sea cucumbers were infected and nearly 20% died. Negative staining showed that the viral particles were detected only in the bodies of the tested animals that were exposed to the viral medium. Histopathologically, the diseased sea cucumbers are characterized by karyopycnosis, and disintegration of the endoplasmic reticula and mitochondria in the epithelial cells in the water-system, the respiratory tree and the alimentary canal.